Most mid-power (D-class to G-class), and high-power (H-class through O-class), model rocket engines were originally custom made and difficult to produce. Technology and manufacturing improvements have made these engines more affordable to produce safely, but are still significantly more expensive than the cardboard cased lower power engines.

To make these engines more affordable, the reloadable model rocket engine was developed. The expensive metal rocket engine casing can be reused, saving much of the component cost. Since the reloads are assembled by the consumer, there is also savings from the labor cost of manufacturing a single-use engine.

Reloadable Motor System

The Reloadable Motor System designed and manufactured by Aerotech is a means to use a reloadable model rocket engine. Often referred to as the RMS, the reloadable motor system is the reusable casing of the reloadable rocket engine.

The reusable reloadable motor system consists of three parts:

The case

The Aft Closure

The Forward Closure

Grease to assist in assuring a tight seal is generally used when reloading the motor system.